diff --git a/README.md b/README.md
index 16698ff..3aa1293 100644
--- a/README.md
+++ b/README.md
@@ -21,6 +21,22 @@ printf("new length: %zu\n", scary_length(a)); //=> 2
 You can push elements with automatic memory extension,
 as much as you want.
 
+Moreover, the `scary_push` is a _generic_ function, so this code
+
+```c
+scary_push(&a, 0UL);
+```
+
+produces a warning by default with modern compilers like GCC 12.
+
+<pre><code>warning: passing argument 1 of ‘scary_push_uint64’ from incompatible pointer type [-Wincompatible-pointer-types]
+    scary_push(&a, 0UL);
+               ^~
+               |
+               int **</code></pre>
+
+You can of course opt-in an option `-Werror` to prevent such typing mistakes.
+
 And you'll see **magic** here:
 
 ```c